The invention relates to an injectable aqueous composition in the form of a gel based on hyaluronic acid or one of the salts thereof, on one or more polyol(s) and on lidocaine, said heat-sterilized composition having improved viscoelastic rheological properties and long in vivo persistence, for use for cosmetic purposes or for therapeutic purposes.
Hyaluronic acid-based injectable gels have been used for many years, for cosmetic purposes, for filling or replacing biological tissues (filling wrinkles, remodeling of the face, increasing lip volume, etc.) and also in treatment to rehydrate the skin by mesotherapy.
Hyaluronic acid-based injectable gels are also used in many therapeutic applications. For example,                in rheumatology, as an agent for replacement or for temporary supplementation of synovial fluid,        in urology/gynecology, as an agent for increasing sphincter volume or urethral volume,        in ophthalmology, as an adjuvant to cataract surgery or for treating glaucoma,        in pharmaceutics, as an agent for release of active substances,        in surgery, for bone reconstruction, increasing vocal cord volume or producing surgical tissues.        
A great deal of effort has been made to improve the physicochemical stability of hyaluronic acid-based gels in order to increase their in vivo persistence (i.e. the residence time of the gel at the injection site) and thus to increase the duration of treatment effectiveness.